||"It seems that all great geniuses have terrible
handwriting," said Ralph, looking at a photograph
of Albert Einstein's signature.
"Hey," thought Wanda to herself, "my teachers
are always complaining that they can't read my
handwriting. If all geniuses have terrible handwriting,
I must be a genius!"
What do you think? Is Wanda really a genius?
If not, what is wrong with her reasoning?
||From the way Wanda uses logic, she's definitely
not a genius. The fact that Individual A shares
one characteristic of a group of individuals does
not logically imply that Individual A is a member
of that group.
Think of it this way. If Ralph had said, "All
whales are good swimmers," Wanda would probably
not have thought to herself, "Hey, I've always
been a good swimmer. I must be a whale!" On the
other hand, if Ralph had said, "All good swimmers
are whales," Wanda would have had to assume either
that she really was a whale or that Ralphie's
statement was false.